Wall construction


Wall construction

Methods for constructing walls for buildings. Walls are constructed in different forms and of various materials to serve several functions. Exterior walls protect the building interior from external environmental effects such as heat and cold, sunlight, ultraviolet radiation, rain and snow, and sound, while containing desirable interior environmental conditions. Walls are also designed to provide resistance to passage of fire for some defined period of time, such as a one-hour wall. Walls often contain doors and windows, which provide for controlled passage of environmental factors and people through the wall line.

Walls are designed to be strong enough to safely resist the horizontal and vertical forces imposed upon them, as defined by building codes. Such loads include wind forces, self-weight, possibly the weights of walls and floors from above, the effects of expansion and contraction as generated by temperature and humidity variations as well as by certain impacts, and the wear and tear of interior occupancy. See Loads, dynamic, Loads, transverse

Modern building walls may be designed to serve as either bearing walls or curtain walls or as a combination of both in response to the design requirements of the building as a whole. Both types may appear similar when complete, but their sequence of construction is usually different.

Bearing-wall construction may be masonry, cast-in-place or precast reinforced concrete, studs and sheathing, and composite types. The design loads in bearing walls are the vertical loading from above, plus horizontal loads, both perpendicular and parallel to the wall plane. Bearing walls must be erected before supported building components above can be erected.

Curtain-wall construction takes several forms, including lighter versions of those used for bearing walls. These walls can also comprise assemblies of corrugated metal sheets, glass panels, or ceramic-coated metal panels, each laterally supported by light subframing members. The curtain wall can be erected after the building frame is completed, since it receives vertical support by spandrel beams, or relieving angles, at the wall line.

Masonry walls are a traditional, common, and durable form of wall construction used in both bearing and curtain walls. They are designed in accordance with building codes and are constructed by individual placement of bricks, blocks of stone, cinder concrete, cut stone, or combinations of these. The units are bonded together by mortar. See Concrete, Masonry, Mortar

Reinforced concrete walls are used for both strength and esthetic purposes. Such walls may be cast in place or precast, and they may be bearing or curtain walls. Some precast concrete walls are constructed of tee-shaped or rectangular prestressed concrete beams, which are more commonly used for floor or roof deck construction. They are placed vertically, side by side, and caulked at adjacent edges. See Concrete beam, Reinforced concrete

Stud and sheathing walls are a light type of wall construction, commonly used in residential or other light construction where they usually serve as light bearing walls. They usually consist of wood sheathing nailed to wood or steel studs, usually with the dimensions 2 × 4 in. (5 × 10 cm) or 2 × 6 in. (5 × 15 cm), and spaced at 16 in. (40 cm) or 24 in. (60 cm) on center—all common building module dimensions. The interior sides of the studs are usually covered with an attached facing material. This is often sheetrock, which is a sandwich of gypsum between cardboard facings. Composite walls are essentially a more substantial form of stud walls. They are constructed of cementitious materials, such as weatherproof sheetrock or precast concrete as an exterior sheathing, and sheetrock as an interior surface finish. See Precast concrete

Prefabricated walls are commonly used for curtain-wall construction and are frequently known as prefab walls. Prefabricated walls are usually made of corrugated steel or aluminum sheets, although they are sometimes constructed of fiber-reinforced plastic sheets, fastened to light horizontal beams (girts) spaced several feet apart. Prefab walls are often made of sandwich construction: outside corrugated sheets, an inside liner of flat or corrugated sheet, and an enclosed insulation are fastened together by screws to form a thin, effective sandwich wall. These usually have tongue-and-groove vertical edges to permit sealed joints when the units are erected at the building site by being fastened to framing girts.

Glass, metal, or ceramic-coated metal panel walls are a common type of curtain wall used in high-rise construction. They are typically assembled as a sandwich by using glass, formed metal, or ceramic-coated metal sheets on the outside, and some form of liner, including possibly masonry, on the inside; insulation is enclosed.

Tilt-up walls are sometimes used for construction efficiency. Here, a wall of any of the various types is fabricated in a horizontal position at ground level, and it is then tilted up and connected at its edges to adjacent tilt-up wall sections. Interior partitions are a lighter form of wall used to separate interior areas in buildings. They are usually nonbearing, constructed as thinner versions of some of the standard wall types; and they are often designed for some resistance to fire and sound. Retaining walls are used as exterior walls of basements to resist outside soil pressure. They are usually of reinforced concrete; however, where the basement depth or exterior soil height is low, the wall may be constructed as a masonry wall. See Buildings, Retaining wall, Structural materials